38-Inhibitors of bacterial cell wall synthesis

Question 1

Alterations in what structure causes bacterial resistance in cell walls?

a) capsid
b) porin
c) polycascharide
d) surface antigen

Answer 1

b) porin

Question 2

What explains the varying sensitivity that beta-lactam bacteria have to antibiotics?

a) strength of the capsule
b) affinity for penicillinase binding protein
c) strength of ionic bonding
d) all of the above

Answer 2

b) affinity for penicillinase binding protein

Question 3

Which is not a beta-lactam drug?

a) Penicillin
b) Cephalosporin
c) Carbanems
d) Monobactam
e) Tetracycline

Answer 3

e) Tetracycline

Question 4

Amoxicillin, Ampicillin, and Piperacillin are all examples of a _________drug?

a) narrow spectrum
b) penicillinase resistant
c) extended spectrum

Answer 4

c) extended spectrum

piperacillin is also antipseudomonal

Question 5

Pencillin is…..

a) narrow spectrum
b) penicillinase resistant
c) extended spectrum

Answer 5

a) narrow spectrum

Question 6

Dicloxacillin and nafcillin…

a) narrow spectrum
b) penicillinase resistant
c) extended spectrum

Answer 6

b) penicillinase resistant

Question 7

Penicillin can cross the blood brain barrier?

a) true
b) false

Answer 7

b) false

Question 8

which is not an indication for giving benzathine, a long acting penicillin?

a) syphillis
b) group a strep
c) rheumatic fever prophylaxis
d) cellulitis

Answer 8

d) cellulitis

Question 9

the aminopenicillins like amoxicillin and ampicillin are good at fighting what type of bacteria?

a) GNCs
b) GPCs
c) Aerobes
d) Anarobes

Answer 9

b) Gram positive cocci

they can fight some enteroccoci and gram negs as well, but not their primary target

Question 10

You are considering giving an aminopenicillin like amox or amp and want to also cover for the other causes of otitis media such as H.Flu and Mcat (both gram neg cocci) as well as URIs and pneumonia, what drug could you add to cover for those?

Answer 10

Amox + Clavulate (Augmentin)

Amp + Sulbactam (Unasyn)

Question 11

a pregnant woman is eating lots of cheese, you are worried for Listeria causing meningitis, what single aminopenicillin would you give to cover her for that bug?

Answer 11

Ampicillin

Question 12

extended spectrum penicillin (combo) for human bites…..

Answer 12

Augmentin or Unasyn

cover everything

Question 13

Ampicillin, is particularly likely to cause a maculopapular rash in patients with certain viral infections, such as……

Answer 13

Mononucleosis

Epstein Barr virus

Question 14

pencillins are relatively safe with a low side effect profile…true or false?

Answer 14

true

Question 15

Piperacillin can fight gram +-, aerobes and anaerobes, but is best against.

a) meningitis
b) diabetic ulcers
c) pseudomonas
d) all of the above

Answer 15

pseudomonas
(piperacillin, ticaracillin are both antipseudomonals)
all renally eliminated

Question 16

super infection with a penicillin resistant organism will likely be what?

a) CRE
b) C Diff
c) Enterocolitis
d) Bacterial endocarditis

Answer 16

b) C Difficile

any abx can cause it, but clinda definately can

Question 17

1st gen cephalosporins treat______, and as you go up the generation ladder, they increase coverage for________?

Answer 17

1st gen treats GPC,

subsequent gens treat gram negs.

Question 18

cephalosporins have less reactions than most drugs, but how are the eliminated?

Answer 18

renally

however, ceftriaxone is excreted in the bile and therefor has a longer halflife

Question 19

what cephalosporin generation treats klebsiella?

Answer 19

1st generation, like Cephalexin (keflex)

Question 20

Lyme disease (gram negative) is treated with what generation cephalosporin?

Answer 20

third gen…ceftriaxone

Question 21

Why should you educate your patients not to drink while on a cephalosporin?

Answer 21

Because the drug + ETOH combo can cause a Disulfiram reaction (the same affects as drinking while on Antabuse….profound n/v)

Question 22

What is the best drug to give someone with pseudomonas and borderline renal failure (hint: its not a penicillin or cephalosporin)?

Answer 22

Aztreonam (A monbactam)
especially useful for PCN allergic patients with pseudomonas as well.
Thats why we give Piperacillin + Tazobactam (Zosyn) both are good against pseudomonas

Question 23

what drug if given alongside your primary drug, can inhibit its excretion and boost serum concentrations of the desired drug (will work well with Carbapenams)?

Answer 23

Probenicid (competes for renal excretion)

Question 24

Carbapenams can INCREASE OR DECREASE seizures thresholds?

Answer 24

Decrease (make it easier to get a seizure)

Question 25

Which of the following will Carbapenams NOT cause?

a) anemia
b) leukopenia
c) thrombocytopenia
d) leukocytosis

Answer 25

d) Leukocytosis

every will drop with carbapenams

Question 26

great drug for necrotizing fasciits (in the “other” category for cell wall synthesis inhibitors)

Answer 26

VANCO

Question 27

VANCO only works in C diff…..

a) IV
b) PO
c) Rectal suppository
d) Intra-thecal

Answer 27

b) PO

Question 28

2 BIG ADR’s for vanco are?

Answer 28

Nephrotoxic
Ototoxic (reversible when stopped)

(especially true when given with aminoglycosides or amphoterrible)

Question 29

You pushed vanco way too fast in an hour, and now they have hypotension and an erythematous rash, what is this called?

Answer 29

Red man syndrome. (Not an allergy, its an infusion rate reaction, just slow the drip)

Question 30

Empiric DOC for sepsis?

Answer 30

Vanco

Question 31

Can bactitracin be used systemically?

Answer 31

of course not